The invention relates to a method for selecting a format for a section to be printed, wherein initially a signature, which comprises pages in a page format of a print product, is disposed on a section to be printed, which comprises the section format, and wherein for producing the print product, the section to be printed is printed and cut, if required, to the signature, and subsequently the signature is collated to form the print product, which is eventually cut to page format.
For producing a multipage print product with generally known print production methods, e.g. in offset-, letterpress-, gravure-, flexo- or digital print, several pages are printed together onto a large format section. For example, a 16-page magazine in DIN A4 format can be printed on a single section in standard format, 63×88 cm (double sided).
In order to produce a print product, the flat paper ware coming from the paper warehouse as a “raw section” is cut, if required, to a section format, which can be processed by the print press, thus to a “section to be printed”. The section to be printed can be cut in the further process of the production of the print product into “partial sections”. Print- or partial sections are folded as “signatures” in the folding machine or in a folding unit or “broken”, and possibly collated into a “raw block”, which is eventually stapled e.g. in a gang stitching binder or in a glue binder in a “bind”, or bound and cut in a block at the remaining edges.
Through variations of said basic principle, the multitude of known bound print products is created. For example, the block for producing a magazine can be provided with a cover made of a heavier paper provided with a more complex imprint. For producing a book, several raw blocks are bound at a common back through thread stitching.
A signature is folded through cross fold or parallel fold. In cross fold, each additional fold of the section is performed transversal to the preceding fold, in parallel fold, each fold is performed parallel to the preceding fold. In zigzag- or leporello fold, the folds are performed in parallel, but in changing direction. In a wrap fold, the folds are performed in parallel and the paper is wound up. A combination of cross fold and parallel fold is designated as mixed fold.
By folding and breaking, the section is partitioned in “running direction”, in which the paper fibers run, and in which the section runs through printing-, folding- and cutting machines, and perpendicular to said direction it is partitioned in “transversal direction”. Said partitioning of the section, which is defined by a fold- and break sequence, is designated by the number of the pages of the print product, respectively disposed subsequent to one another in the running direction of a section, or transversal to said running direction. For example, the partitioning for said production of a 16-page A4 magazine on a standard section 63×88 cm in cross fold is designated “4×2” (4 pages in running direction and 2 pages in transversal direction subsequent to one another).
According to said partitioning, the particular pages of the print product are disposed on the required signatures, so that they appear in the print product in the desired sequence and in the correct orientation after folding and collating. The border areas outside of the pages of the print product on the section to be printed, between adjacent pages and about the pages, are used at least partially for binding at one edge of each page; the others are separated in the context of the production of the print product as “cutoff areas” at the latest during the bookbinding process.
The border areas, in particular the cutoff areas, which are not included any more in the finished print product, offer space for the handlers of the print-, fold- and cutting machines during the production process of the print product, for the initial cut and for various elements to be printed, in particular for cut-, print- and register marks and for color- or grayscale calibration stripes, -bars or -wedges, by means of which the print quality of image printing is checked and the exact color composition is adjusted.
The cutoff area of the first page of a section to be printed thus holds e.g. in book printing traditionally the “section standard”, thus in abbreviated form, the title with the designation of the edition and the section signature with the running number and the number of the print sheets. Other markers facilitate the handling of the imprinted and/or folded section to be printed. Bar shaped “flutter marks” on each completely folded section back facilitate e.g. the intuitive detection of the correct sequence, when collating the signatures into a gang stitching binder. When the sheets are arranged correctly, the flutter marks are visible in a stair case shape. Small “cut marks” on the section to be printed indicate, at which location the section is to be cut or separated, and “fold markers” indicate, how a section is to be folded.
The position of the pages and of the elements to be printed relative to one another on the section to be printed is designated e.g. as “register sheet”, according to Kipphan, handbook of the print media. The selection of formats of the sections to be printed, imposing schemes and register sheets is performed in a generally known manner utilizing highly specialized CAD (computer aided design) systems. Compared to manual layout, such systems have a multitude of advantages. By linking dimensions, CAD systems, on the one hand, offer an automated plausibility control, on the other hand, when a dimension is changed (e.g. the page format), linked dimensions (e.g. the width of the cutoff area, the position and size of a marking) can be automatically adjusted. In particular, imposing schemes can be archived with little effort, and are thus available for later similar applications.
Such a highly specialized CAD system, which supports the manual selection of a format of a section to be printed, by such an archive of specified imposing schemes, is sold e.g. by Kodak und the trade name “upfront”. In the known CAD system, imposing schemes are provided in a library as so-called “section plans”. For each imposing scheme, the particular dimensions of the sections to be printed and of the signatures, of the particular pages of the print product, of the cutoff areas and of the printing elements and of the non printing, and the position and numbering of the pages are defined on the section.
The selection of a format of a section to be printed and the determination of a register sheet for a particular imposing scheme, which is not defined in the library, for an unusual fold sequence resulting from a special format for a print product with a page format, not defined in the library, or with a non-cataloged page number, requires, when using this system in the most favorable case based on an existing scheme, which is as similar as possible, the manual definition of a new register sheet. The selection of several different possible formats of sections to be printed, and based thereon the generation of several different possible imposition schemes and register sheets, and eventually their comparison, in order to optimize the production of a print product under production, logistical and economic considerations is not economical with the known method.
It is the object of the invention to facilitate an automated determination initially of the format of the section to be printed, of the imposition scheme and of the register sheet.